The hand-written nech.ts was always interim; this replaces it with a client
GENERATED from the OpenAPI spec, so the SDK can never drift from the API.

Source-of-truth fixes (the spec drives the ergonomics):
- Clean operationIds on all 13 routes (operation_id="analyzeEmotion" etc.) so
  the generator emits `audio.analyzeEmotion({file})`, not the default
  `analyzeEmotionAnalyzeEmotionPost`. Also cleans /docs.
- One router tag ["audio"] so the generated class is AudioApi, not DefaultApi.
- refresh_openapi.py: the canonical snapshot dump. app.openapi() omits the
  public `servers` block (only injected when served behind root_path), and the
  old README recipe silently dropped it — test_openapi_snapshot guards it, so
  the refresh now injects https://api.nech.pl/audio/v1 itself.

The package (@nech/api, clients/nech-api/):
- typescript-fetch generator → src/audio/ (checked in; regenerate via
  codegen.sh), bundled with tsup to a single ESM file + .d.ts.
- Umbrella package, per-domain SUBPATH exports: `import {AudioApi} from
  '@nech/api/audio'` — one install/version, tree-shakeable, geo/iris slot in as
  siblings later (codegen.sh + exports map have the stubs).
- Build via tsup not bare tsc: the generated code uses extensionless relative
  imports (./runtime) that Node ESM can't resolve from plain tsc output;
  bundling sidesteps it entirely. Verified end-to-end: `@nech/api/audio`
  resolves through the exports map, 13/13 methods present.
- publishConfig + .npmrc point the @nech scope at https://npm.nech.pl.

VERDACCIO.md: copy-paste runbook to stand the private registry up on erable
(container :4873, nginx TLS vhost for npm.nech.pl, seed publisher + lock
signups, publish). NOT yet run — `ssh erable` failed with publickey from the
build host; needs the key loaded. DNS for npm.nech.pl is already set.

README reframed: @nech/api is the official client; nech.ts stays documented as
the working drop-in until the registry is live, then it's retired. Scrubbed a
$DOUANIER_TOKEN codename leak in the curl example. 67 API tests still green.